Notes, summaries, assignments, exams, and exercises for Biology for Baccalaureate

Lymphatic Vessels: Structure and Function

What is the role of a lymphatic vessel? What structure does it have in common with veins?

• Transport: Returns escaped fluid back to the blood.
• Defense: Plays a vital role in disease resistance.
• Structure: Shares the same structural characteristics as veins.

Lymphatics help drain excessive tissue fluid back to the heart. In the microcirculation—consisting of arterioles, capillaries, and veins—fluid filters out into the tissues. Excess fluid not reabsorbed by the veins is delivered back to the heart.

Lymph Gland Functions and Locations

What is the function of a lymph gland? Name two areas where these are in high concentration.

• Filtration: Removes microorganisms, cellular debris, and abnormal cells from lymph

Respiratory System Anatomy

T/F Multi, Match

Upper respiratory: Nose, pharynx

Lower respiratory: Larynx, trachea, bronchi, lungs

Sinuses: Lighten the skull, act as a resonance chamber, and produce mucus.

The Epiglottis and Pharynx

Epiglottis: Consists of 9 pieces of cartilage, including the thyroid cartilage. The epiglottis itself has a stem and leaf structure.

Oropharynx: Extends from the nasal cavity to the larynx. The pharynx is divided into the Nasopharynx, Oropharynx, and Laryngopharynx.

Pleural Cavity: Covered by 2 layers of the pleural membrane. The pleural cavity functions to decrease friction at the lungs.

Mechanics of Ventilation and Respiration

Ventilation: One of the four respiration processes. It is the movement of air into and out of the...

The Human Digestive System

1. The Mouth

• Digestion Initiation: Digestion begins here, involving both mechanical action (chewing) and chemical breakdown (via enzymes).
• Saliva Production: The mouth produces saliva, which is composed of water, mucus, and the enzyme amylase.

2. The Esophagus

The esophagus is a muscular tube connecting the pharynx to the stomach.

• Length and Movement: It is approximately 25 cm long and facilitates the movement of food through peristalsis—a series of rhythmic muscular contractions and relaxations.
• Associated Structures: The passage of food involves the pharynx and the epiglottis, which prevents food from entering the trachea (windpipe).

3. The Stomach

This sac-like organ is involved in both mechanical and chemical digestion....

Neuroscience Notes: Brain Structures and Neural Function

Cells of the Nervous System

Multi CNS

Bi see/hear; Uni touch @ Astro support/nutrients: glucose/lactate/glycogen/scar tissue.

Olig CNS myelin; Micro dead neurons/debris; Schw PNS 1 myelin.

Brain Regions and Meninges

Cl hyp; Na+ out/dep; K+ out; Ca enzyme (dep) @ Pia in/saran wrap.

Sub between pia/arach/brain floats; Arac mid sponge; Dur out/flex @ Temp aud/mem; Crblm motor; Frt plan; Par perc; Occ vis @ Cn. Sulc. between pmc & pssc @ Fis. L gr; Sulc S gr; Gyr bulg @ Thlms sensory brnstm → 4brn/crtx; Hypth endocrn.

4 Fs; Pitu endocrn; Tctm s. colcli vis/i. cocli aud; Tgmtm retic. arous. peri fite/mate red nucl./subs nigra motor control; Pons fibers 4brn → spine; Md.Ob. base of brnstm/vitals....

skeletal system:organ system that includes the bones and the connective tissues that hold the bones together.appendicular skeleton:is the part of your skeleton that is adapted to allow the body to move.axial skeleton:is made up of the bones found in the trunk and head of the body.vertebrae:bones that surround the spinal cord.cartilage:flexible connective tissue that is found between your bones.joint:place where two bones meet.joints classify into:gliding joint(flexibility the wrist and ankle)pivot joint(allows the bones in the neck to move a short distance to left to right)ball-and-socket joint(holds the upper arm and leg to trunk of the body and allows these bones to move in almost any direction)saddle joint(gives bones in the finger the ability...

Invertebrate Chordates: Defining Characteristics

Invertebrate chordates possess several key features, including:

• A notochord
• A dorsal hollow nerve cord
• Gill slits (present at some point in development)
• Muscle blocks (present at some point in development)

They also exhibit fundamental characteristics shared by many complex animals:

• Bilateral symmetry
• A well-developed coelom
• Segmentation

The Notochord

The notochord is a long, semi-rigid, rod-like structure located between the digestive system and the dorsal hollow nerve cord.

• Invertebrate chordates retain this feature throughout life.
• In vertebrates, it is replaced by a backbone during development.
• It develops just after gastrulation from mesoderm tissue on what becomes the dorsal side of the embryo.
• The support

Muscle Contraction Physiology and Rigor Mortis

The Mechanism of Rigor Mortis

Rigor mortis occurs when muscles become rigid a few hours after death. This rigidity results because muscle cells run out of ATP and can no longer pump calcium back into the sarcoplasmic reticulum.

Calcium ions, upon leaving the reticulum, bind to accessory proteins, allowing the formation of cross-bridges. Without ATP, contraction cannot occur, but calcium remains present, and cross-bridges persist, preventing the muscles from stretching. Rigor mortis typically disappears 15 to 20 hours later, when muscle cells begin to break down.

Skeletal Muscle Contraction Control

The nervous system controls the contraction of skeletal muscle. Motor neurons activate specialized synapses...

There are eight fundamental characteristics of the structure of animals that distinguish this group from other groups of living things. These features are:

1. Animals are multicellular. This means that all individuals belonging to the animal kingdom consist of more than one cell, no matter what species they belong to.

   This feature clearly separates the animals from protozoa. Protozoa are a group of unicellular organisms (composed of a single cell) that were formerly classified in the animal kingdom but are now classified in a different group, the kingdom Protozoa, also known as Protista or Protoctista.

2. Animals are eukaryotic. All animals have true cells with nuclei and different organelles in the cytoplasm that perform specific functions. Deoxyribonucleic

Ascent and Transportation of Crude Sap (Xylem)

The rise of crude sap takes place through the xylem vessels in woody plants, usually against gravity. This process requires the presence of several mechanisms that help the sap ascend:

• Root Pressure: Root cells have a much higher concentration of solutes than the external environment. Because of this, water and salts pass into the root by osmosis.

• Transpiration: This is the loss of water by evaporation from leaves and green stems. This loss produces a suction force called tension. The tension is effective due to the high cohesion of water molecules.

• Tension-Cohesion Mechanism: This mechanism prevents the water column from breaking. The high adhesion of water to the vessel walls, together with cohesion,

Allergic Reactions and Hypersensitivity

An allergic reaction occurs when the Immune System (IS) triggers an inappropriate immune response that causes damage to the body's own tissues. This is the development of hypersensitivity within the body.

In cases of rapidly developing hypersensitivity, the reaction occurs between 10 and 20 minutes after exposure to an antigen, which is then specifically called an allergen.

Types of Immunity

Immunity can be broadly categorized based on how it is acquired:

Natural Immunity

Acquired by biological means or inherited from the mother. Examples include:

• Enzymes in tears and skin oils.
• Mucus that traps bacteria and small particles.

Active Immunity

The body produces antibodies in response to the presence of an antigen....